Inverter in diesel engine room -- how bad?

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ranger58sb

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58' Sedan Bridge
I've been studying how/where/when/cost/etc. of a inverter installation. Easiest in this case is to replace an existing charger with an inverter/charger in the same location.

That location is in the engine room, very near but not directly above, the easiest supply battery bank, which is currently (and would continue to be) used for the bow thruster. Nearness to the supply bank addresses manufacturers' distance and fusing recommendations. That location would also simplify AC-side wiring from inverter/charger to the main panel.

Of course the installation manuals say as near the battery bank as possible, but not in an engine room or other hot location. Battery manuals say pretty much the same thing, as do charger manuals. Nor are batteries and chargers supposed to live together in the same location. (All this from a synthesis of Mastervolt, Victron Energy, and ProMariner charger and inverter/charger manuals.)

But then every boat we've ever owned, or even shopped on, has had batteries and chargers in the engine room, direct from the boat manufacturer.

(Our new ride, which is as originally built, currently has 4 battery banks and 3 chargers in our engine room. Not immediately next to the engines, not hugely far away from the genset.)

So, how horrible can it be, placing an inverter/charger in an engine room... along with those other chargers and batteries that aren't supposed to be there either?

Would we says it's:
A) Less optimal than it could be but would work OK
B) Not optimal, but better than nothing
C) really bad
D) dangerous and stupid

Or... maybe we could rate it on a scale of 1-10, with 1 being good enough and 10 being dangerous and stupid...

?????

-Chris
 
The only real issue with putting the inverter in the engine room is heat. As long as the engine room doesn't get hot enough to cause significant inverter de-rating or overheating, it's fine. Worst case, you could always build a box around an inverter or battery bank and vent it to the outside to keep things cooler. For batteries, unless you're running long travel day after long travel day, protecting them from radiant heat will help a lot.

My house bank, inverter, and solar controllers are outside of the engine room (although I'd have to move the house bank into the engine room if I ever make it bigger, mostly for weight distribution). The start batteries and charger are in the engine room, however, with no issues.

Batteries and inverters can live together, just don't put the inverter above the batteries (especially if they're flooded) where it'll receive all of the battery off-gassing. With some ventilation, the inverter off to the side and especially if you're using AGM, gel, or lithium batteries then having both in the same compartment is no problem.
 
Victron publishes derating curves. For a 104F engine room, the maximum continuous power from a 3kW MultiPlus inverter/charger is 2.2kW.
 
My Magnum 2800W inverter charger is in the ER. Not ideal but then I have a single engine boat and my engine coolant temp stays at a constant 174 degrees. So hot, but the ER doesn't get super hot.


When I'm under way, I'm not charging the battery with the charger. I'm also not typically running a lot of 120volt loads. The refer is running on 12v when under way and I'm not heating water.
 
My Magnum Energy inverter charger is in the engine room. During the refit process, I added exhaust ventilation to keep the temperature down. The thermometer is close to the ceiling and rarely shows temperature above 110 degrees. What the temperature is at the batteries and inverter is probably significantly less. If you plan to do what I did as far as added ventilation, remember to increase incoming air vents to prevent starving the engine or generator.

Ted
 
My Magnum 2800W inverter charger is in the ER. Not ideal but then I have a single engine boat and my engine coolant temp stays at a constant 174 degrees. So hot, but the ER doesn't get super hot.

When I'm under way, I'm not charging the battery with the charger. I'm also not typically running a lot of 120volt loads. The refer is running on 12v when under way and I'm not heating water.


My Xantrex manual says to try to keep the temp under 50°C (122°F).
Never been an issue.
I too can't use the charger while under way, rarely use the inverter feature.
 
Unless the engine room gets excessively hot, its no big deal to install an inverter/charger in the engine room. If it is a gas boat, DON'T DO IT.
 
I have a pair of stacked Victron multiplus 3KW inverter/chargers in the engine room, and they work just fine
 
My survey made me inverter/charger it out. It was installed in engine room when I n=bought the boat. Anyone have ABYC on this?
 
I recently went with a LiFePO4 bank and moved my house bank and inverter from the ER to the aft lazarette. My goal was twofold: free-up ER space; and put the LFP batteries in an out-of-way place. Heat was not a concern - engine rooms I've been in have been hot but not overwhelmingly so, even in the tropics. I'd hazard a guess the OEM cautions were rooted in lawyers unsure of how people would configure their system. FLA batteries off-gas, inverters are generally NOT ignition protected so presence of gasoline would be a huge hazard.

Unless OP has a strong desire to move the batteries and inverter/charger, I'd keep it as-is. By far, biggest config issue remains long cable runs that foster voltage drop (and heat) so keeping them close to one another is a top priority.

Peter
 
Besides derating for ER temperature , the inverter will have a hard life if directly over the charging batt set.
Not just hydrogen comes up out of a batt being heavily charged.
 
Thanks, all

Hadn't found Victron's de-rating charts, so seeing those helps. The fact they exist seems to confirm engine room temps not optimal but not dangerous. Check.

Diesel, not gas, check.

Not located directly over the batteries. Check.

Additional ventilation, hmmmmm... have to look further into that.

-Chris
 
Sometimes just increasing air circulation to the device will improve cooling. A couple of small fans aimed at the inverter would help. THey could be activated by a temp. sensitive switch.
The bilge is almost always much cooler than the top of the E.R. Set the fans low so they pick up that cooler air even if some small ducting is needed.
 
I've sold 8 or 9 inverters and other electronic components to boaters whose electronics in the engine room was destroyed by an exhaust hose leak which sprayed salt spray or steam on everything. A few of those were from generator exhaust leaks.

None were repairable due to the quick corrosion of the electronic components.

I have no electronics of any kind in the engineroom. If I experience an exhaust leak, I repair the leak, wash the entire engine room and can continue my cruise.

With electronics dead from salt water in the ER, the cruise may not be continued depending on whats installed down there.
 
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Anything in the seawater circuit should be replaced well in advance of failure underway. That being said sh#% sometimes happens even to the most dilligent. The ER may well be tge popular place for these components, heck on some boats, the only place. If you have another viable location, great. But most will still have to be in there.
 
Anything in the seawater circuit should be replaced well in advance of failure underway. That being said sh#% sometimes happens even to the most dilligent. The ER may well be tge popular place for these components, heck on some boats, the only place. If you have another viable location, great. But most will still have to be in there.

That is the challenge for most boats in the size range generally found in recreational boats.

No dedicated space for electrical components.

That leaves little choice except for the engine room.
 
For the OP, your box "A" is about right. If you can put inverter/charger elsewhere then do it. Of less concern is house bank, but likewise not in ER if possible.

My Victron Quattro 3000 and house bank are in the ER. I've had the Quattro de-rate to the point where the dryer trips it if I use it underway. Washing machine is ok.
Of course there are other AC loads underway, including my nav PC which takes 600W.
Unfortunate, as underway the large alternators can provide plenty of juice. I checked a couple of times and the Quattro was a bit over 50°C
 
Inverter in Engine Room

I have '89 Grand Banks. Original inverter was in the engine room (3208's). No problem. Have replaced it in same location....no problem.
 
invertor in the engine room

Hello i had a 5kw victron invertor in the engine room, it was no problem so long we didt make a longer trip, during travel the engine room got 40gr C. but when we stoped the temp rise to 60 gr C.
then the invertors reduse the max output to 25% or shut down completly

the just stop working, when the engine room was cool again the started back working

So i replaced the invertor in the next room and no problem anny more.

If you have big engines (in size) the heat comes when you stop them the block have 70 or 80gr C and there is no extra airflow in the engine room, so it starts heating up.

measure the temp in your engine room , so you now if it could be a problem

Best regards,
Patrick

ps on my current boat i changed one shower room to elektrical room so all heavy electronic equipment can stay cool, i also put a temp controled fan to get rid af the warm air in the room
 
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Hello i had a 5kw victron invertor in the engine room, it was no problem so long we didt make a longer trip, during travel the engine room got 40gr C. but when we stoped the temp rise to 60 gr C.
then the invertors reduse the max output to 25% or shut down completly

the just stop working, when the engine room was cool again the started back working

So i replaced the invertor in the next room and no problem anny more.

If you have big engines (in size) the heat comes when you stop them the block have 70 or 80gr C and there is no extra airflow in the engine room, so it starts heating up.


Thanks, that's a useful reminder. Our engine room does indeed stay hot after running for a while.

-Chris
 
Also, be aware that not only does the inverter side of an inverter/charger degrade with heat, so does the charger side. For the most efficient charging, check your unit's specs on output/temp rating. A 25% degrade is not unusual at some normal engine room temps or temps reached if your unit is a cabinet.

Tator
 

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